1/*
2 * Copyright (c) Intel Corp. 2007.
3 * All Rights Reserved.
4 *
5 * Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
6 * develop this driver.
7 *
8 * This file is part of the Carillo Ranch video subsystem driver.
9 * The Carillo Ranch video subsystem driver is free software;
10 * you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * The Carillo Ranch video subsystem driver is distributed
16 * in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this driver; if not, write to the Free Software
23 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
24 *
25 * Authors:
26 *   Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
27 *   Alan Hourihane <alanh-at-tungstengraphics-dot-com>
28 */
29
30#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31
32#include <linux/module.h>
33#include <linux/kernel.h>
34#include <linux/init.h>
35#include <linux/platform_device.h>
36#include <linux/mutex.h>
37#include <linux/fb.h>
38#include <linux/backlight.h>
39#include <linux/lcd.h>
40#include <linux/pci.h>
41#include <linux/slab.h>
42
43/* The LVDS- and panel power controls sits on the
44 * GPIO port of the ISA bridge.
45 */
46
47#define CRVML_DEVICE_LPC    0x27B8
48#define CRVML_REG_GPIOBAR   0x48
49#define CRVML_REG_GPIOEN    0x4C
50#define CRVML_GPIOEN_BIT    (1 << 4)
51#define CRVML_PANEL_PORT    0x38
52#define CRVML_LVDS_ON       0x00000001
53#define CRVML_PANEL_ON      0x00000002
54#define CRVML_BACKLIGHT_OFF 0x00000004
55
56/* The PLL Clock register sits on Host bridge */
57#define CRVML_DEVICE_MCH   0x5001
58#define CRVML_REG_MCHBAR   0x44
59#define CRVML_REG_MCHEN    0x54
60#define CRVML_MCHEN_BIT    (1 << 28)
61#define CRVML_MCHMAP_SIZE  4096
62#define CRVML_REG_CLOCK    0xc3c
63#define CRVML_CLOCK_SHIFT  8
64#define CRVML_CLOCK_MASK   0x00000f00
65
66static struct pci_dev *lpc_dev;
67static u32 gpio_bar;
68
69struct cr_panel {
70	struct backlight_device *cr_backlight_device;
71	struct lcd_device *cr_lcd_device;
72};
73
74static int cr_backlight_set_intensity(struct backlight_device *bd)
75{
76	int intensity = bd->props.brightness;
77	u32 addr = gpio_bar + CRVML_PANEL_PORT;
78	u32 cur = inl(addr);
79
80	if (bd->props.power == FB_BLANK_UNBLANK)
81		intensity = FB_BLANK_UNBLANK;
82	if (bd->props.fb_blank == FB_BLANK_UNBLANK)
83		intensity = FB_BLANK_UNBLANK;
84	if (bd->props.power == FB_BLANK_POWERDOWN)
85		intensity = FB_BLANK_POWERDOWN;
86	if (bd->props.fb_blank == FB_BLANK_POWERDOWN)
87		intensity = FB_BLANK_POWERDOWN;
88
89	if (intensity == FB_BLANK_UNBLANK) { /* FULL ON */
90		cur &= ~CRVML_BACKLIGHT_OFF;
91		outl(cur, addr);
92	} else if (intensity == FB_BLANK_POWERDOWN) { /* OFF */
93		cur |= CRVML_BACKLIGHT_OFF;
94		outl(cur, addr);
95	} /* anything else, don't bother */
96
97	return 0;
98}
99
100static int cr_backlight_get_intensity(struct backlight_device *bd)
101{
102	u32 addr = gpio_bar + CRVML_PANEL_PORT;
103	u32 cur = inl(addr);
104	u8 intensity;
105
106	if (cur & CRVML_BACKLIGHT_OFF)
107		intensity = FB_BLANK_POWERDOWN;
108	else
109		intensity = FB_BLANK_UNBLANK;
110
111	return intensity;
112}
113
114static const struct backlight_ops cr_backlight_ops = {
115	.get_brightness = cr_backlight_get_intensity,
116	.update_status = cr_backlight_set_intensity,
117};
118
119static void cr_panel_on(void)
120{
121	u32 addr = gpio_bar + CRVML_PANEL_PORT;
122	u32 cur = inl(addr);
123
124	if (!(cur & CRVML_PANEL_ON)) {
125		/* Make sure LVDS controller is down. */
126		if (cur & 0x00000001) {
127			cur &= ~CRVML_LVDS_ON;
128			outl(cur, addr);
129		}
130		/* Power up Panel */
131		schedule_timeout(HZ / 10);
132		cur |= CRVML_PANEL_ON;
133		outl(cur, addr);
134	}
135
136	/* Power up LVDS controller */
137
138	if (!(cur & CRVML_LVDS_ON)) {
139		schedule_timeout(HZ / 10);
140		outl(cur | CRVML_LVDS_ON, addr);
141	}
142}
143
144static void cr_panel_off(void)
145{
146	u32 addr = gpio_bar + CRVML_PANEL_PORT;
147	u32 cur = inl(addr);
148
149	/* Power down LVDS controller first to avoid high currents */
150	if (cur & CRVML_LVDS_ON) {
151		cur &= ~CRVML_LVDS_ON;
152		outl(cur, addr);
153	}
154	if (cur & CRVML_PANEL_ON) {
155		schedule_timeout(HZ / 10);
156		outl(cur & ~CRVML_PANEL_ON, addr);
157	}
158}
159
160static int cr_lcd_set_power(struct lcd_device *ld, int power)
161{
162	if (power == FB_BLANK_UNBLANK)
163		cr_panel_on();
164	if (power == FB_BLANK_POWERDOWN)
165		cr_panel_off();
166
167	return 0;
168}
169
170static struct lcd_ops cr_lcd_ops = {
171	.set_power = cr_lcd_set_power,
172};
173
174static int cr_backlight_probe(struct platform_device *pdev)
175{
176	struct backlight_properties props;
177	struct backlight_device *bdp;
178	struct lcd_device *ldp;
179	struct cr_panel *crp;
180	u8 dev_en;
181
182	lpc_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
183					CRVML_DEVICE_LPC, NULL);
184	if (!lpc_dev) {
185		pr_err("INTEL CARILLO RANCH LPC not found.\n");
186		return -ENODEV;
187	}
188
189	pci_read_config_byte(lpc_dev, CRVML_REG_GPIOEN, &dev_en);
190	if (!(dev_en & CRVML_GPIOEN_BIT)) {
191		pr_err("Carillo Ranch GPIO device was not enabled.\n");
192		pci_dev_put(lpc_dev);
193		return -ENODEV;
194	}
195
196	memset(&props, 0, sizeof(struct backlight_properties));
197	props.type = BACKLIGHT_RAW;
198	bdp = devm_backlight_device_register(&pdev->dev, "cr-backlight",
199					&pdev->dev, NULL, &cr_backlight_ops,
200					&props);
201	if (IS_ERR(bdp)) {
202		pci_dev_put(lpc_dev);
203		return PTR_ERR(bdp);
204	}
205
206	ldp = devm_lcd_device_register(&pdev->dev, "cr-lcd", &pdev->dev, NULL,
207					&cr_lcd_ops);
208	if (IS_ERR(ldp)) {
209		pci_dev_put(lpc_dev);
210		return PTR_ERR(ldp);
211	}
212
213	pci_read_config_dword(lpc_dev, CRVML_REG_GPIOBAR,
214			      &gpio_bar);
215	gpio_bar &= ~0x3F;
216
217	crp = devm_kzalloc(&pdev->dev, sizeof(*crp), GFP_KERNEL);
218	if (!crp) {
219		pci_dev_put(lpc_dev);
220		return -ENOMEM;
221	}
222
223	crp->cr_backlight_device = bdp;
224	crp->cr_lcd_device = ldp;
225	crp->cr_backlight_device->props.power = FB_BLANK_UNBLANK;
226	crp->cr_backlight_device->props.brightness = 0;
227	cr_backlight_set_intensity(crp->cr_backlight_device);
228	cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_UNBLANK);
229
230	platform_set_drvdata(pdev, crp);
231
232	return 0;
233}
234
235static int cr_backlight_remove(struct platform_device *pdev)
236{
237	struct cr_panel *crp = platform_get_drvdata(pdev);
238
239	crp->cr_backlight_device->props.power = FB_BLANK_POWERDOWN;
240	crp->cr_backlight_device->props.brightness = 0;
241	crp->cr_backlight_device->props.max_brightness = 0;
242	cr_backlight_set_intensity(crp->cr_backlight_device);
243	cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_POWERDOWN);
244	pci_dev_put(lpc_dev);
245
246	return 0;
247}
248
249static struct platform_driver cr_backlight_driver = {
250	.probe = cr_backlight_probe,
251	.remove = cr_backlight_remove,
252	.driver = {
253		   .name = "cr_backlight",
254		   },
255};
256
257static struct platform_device *crp;
258
259static int __init cr_backlight_init(void)
260{
261	int ret = platform_driver_register(&cr_backlight_driver);
262
263	if (ret)
264		return ret;
265
266	crp = platform_device_register_simple("cr_backlight", -1, NULL, 0);
267	if (IS_ERR(crp)) {
268		platform_driver_unregister(&cr_backlight_driver);
269		return PTR_ERR(crp);
270	}
271
272	pr_info("Carillo Ranch Backlight Driver Initialized.\n");
273
274	return 0;
275}
276
277static void __exit cr_backlight_exit(void)
278{
279	platform_device_unregister(crp);
280	platform_driver_unregister(&cr_backlight_driver);
281}
282
283module_init(cr_backlight_init);
284module_exit(cr_backlight_exit);
285
286MODULE_AUTHOR("Tungsten Graphics Inc.");
287MODULE_DESCRIPTION("Carillo Ranch Backlight Driver");
288MODULE_LICENSE("GPL");
289